There is diversity in the timing and manner of cell division throughout the embryo’s development. While scientists once viewed this diversity as a challenge to be managed, a new finding from the Hiiragi team suggests that it actually supports healthy growth.
There is diversity in the timing and manner of cell division during embryo development. Previously, researchers viewed this diversity as a challenge to be managed, but the Hiiragi team has discovered that it actually fosters healthy development. Their findings, published in Science on October 11, 2024, encourage a reevaluation of the role of variability and could greatly influence assisted reproductive technologies.
An embryo is made up of cells that divide to create new cells, contributing to the embryo’s growth. These cells show variability in their division timing and the ways they interact with each other. Traditionally, scientists thought this variability hindered proper embryo development and should be minimized. However, the Hiiragi team’s recent study published in Science challenges this notion.
Embryo Development
“We discovered that the unpredictability in cell division timing and methods can actually aid in the proper development of embryos,” states Dimitri Fabrèges, a postdoctoral researcher from the Hiiragi group. The team examined mouse, rabbit, and monkey embryos and were astonished by their findings. “Regardless of the random nature of cell division timings, the embryos managed to develop organized and functional structures,” Fabrèges clarifies.
Cell Interaction
As cells divide and create new cells, the embryo expands. Hence, all cells must reorganize within the growing embryo to establish a structured formation. The Hiiragi team employed tools known as morphomaps to observe how cells position themselves during development. Moreover, they studied the physical interactions between the cells to understand how they create a connected structure—referred to as topology—and how this evolves over time within the embryo.
Supporting Healthy Development
The team found that increased variability in cell division contributes to a better arrangement of cells within the embryo, which supports healthy growth. “Our findings indicate that variability in both the timing and methods of cell division—and the interactions between cells—are not just accepted during development; they actively contribute to robust growth,” Fabrèges explains.
Embryo Well-Being
The implications of these discoveries challenge longstanding beliefs. “The significance of variability in embryonic development has often been underestimated in our research area. However, we demonstrate that it actually enhances the precision and durability of tissue development,” remarks Fabrèges. He and his research team hope their study will inspire other scientists to recognize the advantages of variability. “It’s conceivable that variability and topology could serve as reliable indicators of an embryo’s health, potentially transforming assisted reproductive technologies,” he concludes.
